I cant find a place to hook up my cab lights on my '05. I looked on the passenger side dash where the plugs are and there is no factory hookup there. Any ideas?

Here's a link for Cab Light installation. It was written for earlier years, but I believe it will work on your 05.
Post #36 has a link showing where to get +12V and Grd in Fuse Block Right of Instrument Panel.
http://www.dieselplace.com/forum/showthread.php?t=4434&highlight=light

In link below, page B-13 and page D-161 shows wiring. Looks like connector #6, pin "B" is +12V. Verify with a test light or VOM.
http://www.gmupfitter.com/publicat/2004_BB/2003_Beyond_LD_Electric_CK.pdf

If you're looking at the passenger side box, look bottom left from outside the truck in the slot for a electrical plug. There is a ground prong, full power prong (always on), and one that comes on with the parking lights. I grounded mine inside the roof to a support (didn't use gm harness and plug) and ran the power down the pillar to the box. I then put on a female spade connector on my hot wire crimped it a bit extra and slid it on the prong in the box.

I have had mine like this since October and have not had any issues with them. Just use a test light to see which prong is which. If you still need help, I can look later at which prong mine is on and possibly grab a pic for you.

That was it. Got it connected today. Thanks